| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a brazing joint structure, and a joining method for metal piping capable of maintaining a necessary brazing clearance even when brazing two pipe materials with a difference in linear expansion coefficients. <P>SOLUTION: In a joint part 6 constituted by inserting a reduced part 2 of inscribed side piping 1 into an expanded part 4 of circumscribed side piping 3 having a vertical groove 5 on an inner face, the circumscribed side piping 3 and the inscribed side piping 1 are brazed together. If a linear expansion coefficient of the circumscribed side piping 3 is larger than a linear expansion coefficient of the inscribed side piping 1, the expanded part 4 is expanded more than the reduced part 2 by heating during joining, and the joint part 6 is deformed in a separating direction of an reduced part 2 outer face and an expanded part 4 inner face. Even in such a case, by the brazing joint structure, the reduced part 2 is inserted deeper into the expanded part 4 inner face by self-weight of the inscribed side piping 1 and a pressure by a pressurizing mechanism, and the expanded part 4 inner face and the reduced part 2 outer face are closely adhered again. By this, a depth of the vertical groove 5 of a closely adhered portion becomes the brazing clearance, a stable brazing flow can be achieved, and highly reliable brazing can be carried out. <P>COPYRIGHT: (C)2012,JPO&INPIT |
